The bill still needs Mayor Slay's signature, which it is expected to get, before LA-based festival organizer International Creative Management Partners can begin negotiating for talent and financing. The bill was passed 21-4; here is the breakdown of votes:

ICM released a statement Monday morning, saying it was pleased with the vote.

"Today's vote marks an important milestone in bringing world-class festivals to St. Louis to create vibrant new music experiences in the region," spokeswoman Michelle Suess said in the statement. "With the backdrop of the historic Gateway Arch and the shores of the Mississippi River, the festivals will bring together top-tier music acts from a variety of genres with local musicians, who are an integral part of the cultural fabric of the city."

The bill states that Summer Rocks must pay the city $50,000 per festival for the first ten years of a proposed twenty-year deal. ICM must also pay up to $400,000 per festival for services from the city.

Beyond that is a tiered system that would net the city 1 percent of ticket fees if more than 30,000 are sold, 10.5 percent if more than 90,000 are sold and 15 percent if the festivals stay in place for the full twenty years.

The festivals will take place on Memorial and Labor Day weekends each year. One is intended to be a major rock festival, and the other will feature predominantly country artists. The first events could take place as early as 2015.